Battery monitoring system, battery monitoring device, battery control device

Abstract

To provide a battery monitoring system that can perform proper wireless communication between a battery control device and a battery monitoring device even if a wireless communication environment changes, the battery monitoring device forming the battery monitoring system, and the battery control device forming the battery monitoring system.SOLUTION: In a housing section of a housing 50, each battery block 21, each battery monitoring device 30, and a battery control device 40 are accommodated. A slave unit-side antenna of each battery monitoring device 30 is configured such that a radio wave directivity can be selected from among a plurality of radio wave directivities in which the direction of the center of the radio wave directivity is different. In a channel used for wireless communication between a master unit-side antenna and slave unit-side antenna of the battery control device 40, the radio wave directivity of the slave unit-side antenna is set to a radio wave directivity other than the radio wave directivity that provides the lowest communication quality of wireless communication among the various radio wave directivities.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a battery monitoring system, a battery monitoring device constituting the battery monitoring system, and a battery control device constituting the battery monitoring system. [Background technology]

[0002] A battery monitoring system is known that includes a battery control device and a battery monitoring device that is provided for each of a plurality of batteries and monitors the state of the batteries. The battery control device has a parent antenna for wireless communication with the battery monitoring device, and each battery monitoring device has a child antenna for wireless communication with the battery control device.

[0003] Each battery, each battery monitoring device, and the battery control device are housed in a housing section. The housing section is configured so that at least a portion of the housing section reflects radio waves. Therefore, when the battery monitoring device transmits a wireless signal, the transmitted wireless signal is reflected by the wall of the housing section. As a result, multipath occurs, and accurate information may not be transmitted from the battery monitoring device to the battery control device.

[0004] To address such problems, Patent Document 1 describes a configuration in which at least one of the parent unit antenna and the child unit antenna is a directional antenna that radiates radio waves more strongly in a predetermined directional direction than in a predetermined non-directional direction. The directional antenna radiates radio waves more strongly in a direction along the surface of the battery on which the battery control device or the battery monitoring device is installed than in a direction perpendicular to the surface of the battery on which the battery control device or the battery monitoring device is installed. This allows the radio wave directivity of the directional antenna to improve the wireless communication environment between the battery control device and the battery monitoring device in the storage section, and allows accurate information to be transmitted from the battery monitoring device to the battery control device. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6996574 Summary of the Invention [Problem to be solved by the invention]

[0006] The wireless communication environment between the battery control device and the battery monitoring device in the storage unit may change, so even if accurate information can be transmitted between the battery monitoring device and the battery control device in one wireless communication environment, accurate information may not be transmitted in another wireless communication environment.

[0007] The main object of the present invention is to provide a battery monitoring system that can perform appropriate wireless communication between a battery control device and a battery monitoring device even if the wireless communication environment changes, a battery monitoring device that constitutes the battery monitoring system, and a battery control device that constitutes the battery monitoring system. [Means for solving the problem]

[0008] The present invention includes a battery monitoring device provided in correspondence with each of a plurality of batteries and monitoring the state of the batteries; A battery control device, In a battery monitoring system in which the batteries, the battery monitoring devices, and the battery control device are accommodated in a housing configured to reflect radio waves at least in part, the battery control device has a parent device-side antenna for wireless communication with the battery monitoring device, Each of the battery monitoring devices has a slave-side antenna for wireless communication with the battery control device, At least one of the radio wave directivities of the radio wave directivities of the antennas on the child device side and the radio wave directivities of the antennas on the parent device side is configured to be selectable from a plurality of radio wave directivities having different directions of the center of the radio wave directivities; In a channel used for wireless communication between the parent device side antenna and the child device side antenna, the radio wave directivity is set to one of the radio wave directivities other than the radio wave directivity that provides the lowest communication quality of the wireless communication.

[0009] Even if accurate information cannot be transmitted between a battery monitoring device and a battery control device in a certain wireless communication environment, accurate information can be transmitted between the battery monitoring device and the battery control device by changing the direction of the center of the antenna's radio wave directivity.

[0010] In view of this, in the present invention, at least one of the radio wave directivities of the radio wave antennas on the child device side and the parent device side antenna is configured to be selectable from a plurality of radio wave directivities having different directions of the center of the radio wave directivities. Based on this configuration, in a channel used for wireless communication between the parent device side antenna and the child device side antenna, the radio wave directivities are set to a radio wave directivity other than the radio wave directivity that provides the lowest communication quality of wireless transmission. This allows proper wireless communication to be performed between the battery control device and the battery monitoring device even if the wireless communication environment changes.

[0011] In addition, in the channel, being set to a radio wave directivity among the respective radio wave directivities other than the radio wave directivity that provides the lowest communication quality of the wireless transmission means, specifically, for example, being set to a radio wave directivity among the respective radio wave directivities among the respective radio wave directivities in the channel such that the received power of the battery control device or the battery monitoring device when the wireless communication is performed is equal to or greater than a threshold value. [Brief description of the drawings]

[0012] [Figure 1] 1 is a configuration diagram of a vehicle according to a first embodiment. [Diagram 2] FIG. 2 is a block diagram showing a battery pack. [Diagram 3] FIG. 4 is a perspective view showing an arrangement of a battery block and the like in a housing. [Figure 4] Cross-sectional view taken along line 4-4 in Figure 3. [Diagram 5] FIG. 2 is a diagram showing an arrangement of battery cells that form a battery block. [Figure 6] FIG. 1 shows a configuration capable of switching between two radio wave directivities. [Figure 7]1 is a diagram showing frequency characteristics of received power corresponding to radio wave directivities A and B. FIG. [Figure 8] FIG. 4 is a diagram showing interference between a main wave and a reflected wave. [Figure 9] 4 is a time chart showing the transition of a main wave, a reflected wave, and a composite wave thereof; [Figure 10] FIG. 13 is a diagram showing the correspondence between radio wave directivity at which the received power is maximum and each channel. [Figure 11] 10 is a flowchart showing the procedure of a process for generating map information that links each channel with the radio wave directivity that maximizes the received power. [Figure 12] 5 is a flowchart showing the procedure of a process for switching radio wave directivity executed by the battery monitoring device. [Figure 13] FIG. 1 is a diagram showing an example of an antenna whose directivity can be changed; [Figure 14] FIG. 1 is a diagram showing an example of an antenna whose directivity can be changed; [Figure 15] FIG. 1 is a diagram showing an example of an antenna whose directivity can be changed; [Figure 16] FIG. 13 is a diagram showing an antenna according to a comparative example. [Figure 17] FIG. 16 is a diagram showing a modification of the configuration shown in FIG. [Figure 18] FIG. 1 is a diagram showing how a battery can be reused from an in-vehicle application to a stationary application. [Figure 19] FIG. 13 is a diagram showing frequency characteristics of received power in an in-vehicle application. [Figure 20] FIG. 13 is a diagram showing frequency characteristics of received power in stationary applications. [Figure 21] FIG. 13 is a diagram showing frequency characteristics of received power when the radio wave directivity of each channel is reset in a stationary application. [Figure 22] FIG. 13 is a diagram showing frequency characteristics of received power before switching radio wave directivity. [Diagram 23] FIG. 11 is a diagram showing frequency characteristics of received power after switching radio wave directivity. [Figure 24] 6 is a flowchart showing a procedure for switching processing of radio wave directivity when an abnormality occurs. [Diagram 25]FIG. 13 is a perspective view showing an arrangement of a battery block and the like in a housing according to a modified example of the first embodiment. [Figure 26] 10 is a flowchart showing the procedure of a process for generating map information in which radio wave directivity with maximum received power is associated with each channel according to the second embodiment. [Figure 27] 5 is a flowchart showing the procedure of a process for switching radio wave directivity executed by the battery control device. [Figure 28] FIG. 11 is a diagram showing the overall configuration of an inspection system including a mobile terminal, a server, and the like according to a third embodiment. [Figure 29] 10 is a flowchart showing the procedure of a process for generating map information that links each channel with the radio wave directivity that maximizes the received power. [Diagram 30] 13 is a flowchart showing the procedure of a process for generating map information in which radio wave directivity with maximum received power is associated with each channel according to the fourth embodiment. [Diagram 31] FIG. 11 is a diagram showing an example of a specific condition. [Diagram 32] 13 is a flowchart showing the procedure of a process for generating map information in which radio wave directivity with maximum received power is associated with each channel according to the fifth embodiment. [Diagram 33] FIG. 13 is a perspective view showing the arrangement of the battery block and other components in the housing when an abnormality occurs according to the sixth embodiment. [Diagram 34] 10 is a flowchart showing the procedure of a process for generating map information that links each channel with the radio wave directivity that maximizes the received power. [Diagram 35] FIG. 23 is a characteristic diagram showing the relationship between each channel, a communication error rate, and radio wave directivity according to the seventh embodiment. [Diagram 36] 10 is a flowchart showing the procedure of a process for generating map information that associates each channel with the radio wave directivity that minimizes the communication error rate. [Figure 37] FIG. 23 is a characteristic diagram showing the relationship between each channel and the difference between the received power and the noise floor according to the eighth embodiment. [Figure 38] FIG. 11 is a characteristic diagram showing the relationship between each channel and the difference between the received power and the noise floor. [Figure 39]11 is a flowchart showing the steps of a process for generating map information that links each channel with the radio wave directivity that maximizes the difference between the received power and the noise floor. [Diagram 40] FIG. 13 is a diagram showing an arrangement of battery packs in an accommodation space within a chassis of a vehicle according to a ninth embodiment. [Diagram 41] Cross-sectional view of line 41-41 in Figure 40. [Diagram 42] FIG. 23 is a cross-sectional view of a battery pack according to a tenth embodiment. [Diagram 43] FIG. 23 is a cross-sectional view of a battery pack according to an eleventh embodiment. [Diagram 44] FIG. 23 is a diagram showing an arrangement of batteries in an accommodation space within a chassis of a vehicle according to a twelfth embodiment. [Diagram 45] FIG. 13 is a perspective view showing a battery according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Several embodiments will be described with reference to the drawings. In several embodiments, functionally and / or structurally corresponding and / or associated parts may be given the same reference numerals. For corresponding and / or associated parts, the description of other embodiments may be referred to.

[0014] First Embodiment DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A battery monitoring system according to a first embodiment of the present invention will now be described with reference to the drawings. The battery monitoring system is mounted on a vehicle such as an electric vehicle or a hybrid vehicle that uses a rotating electric machine as a power source for running.

[0015] 1 is a diagram showing a schematic configuration of a vehicle 10. The vehicle 10 includes a battery pack 11, a power control unit (hereinafter, referred to as "PCU") 12, a motor 13, and a vehicle ECU .

[0016] The battery pack 11 is mounted on the vehicle 10 as a driving power source for the vehicle 10. Specifically, the battery pack 11 is mounted, for example, in an engine room, a trunk room, under a seat, or under a floor of the vehicle 10. The vehicle 10 runs using the power stored in the battery pack 11.

[0017] As shown in Fig. 2, the battery pack 11 includes an assembled battery 20 including a series connection of a plurality of battery cells 22 (specifically, secondary cells). The assembled battery 20 stores power for driving the motor 13 and can supply power to the motor 13 via the PCU 12. The assembled battery 20 is charged by receiving power generated by the motor 13 via the PCU 12 when the motor 13 generates regenerative power during braking of the vehicle 10, for example. The assembled battery 20 can be connected to an external charger CM provided outside the vehicle 10, as shown in Fig. 1. The external charger CM is, for example, a stationary facility. The assembled battery 20 is charged from the external charger CM.

[0018] The PCU 12 performs bidirectional power conversion between the battery pack 11 and the motor 13 based on a control signal from the vehicle ECU 14. The PCU 12 includes, for example, an inverter that drives the motor 13, and a converter that boosts the DC voltage supplied to the inverter to an output voltage of the battery pack 11 or higher.

[0019] The motor 13 is an AC rotating electric machine, for example a three-phase AC synchronous motor with a permanent magnet embedded in the rotor. The motor 13 is driven by the PCU 12 to generate a rotational driving force, and the driving force generated by the motor 13 is transmitted to the driving wheels of the vehicle 10. On the other hand, when the vehicle 10 is braked, the motor 13 operates as a generator and generates regenerative electricity. The electric power generated by the motor 13 is supplied to the battery pack 11 via the PCU 12 and stored in the battery pack 20 in the battery pack 11.

[0020] The vehicle ECU 14 includes a CPU, a ROM, a RAM, and input / output ports for inputting and outputting various signals. The CPU loads a program stored in the ROM into the RAM and executes it. The program stored in the ROM describes the processing of the vehicle ECU 14. As an example of the main processing of the vehicle ECU 14, the vehicle ECU 14 receives information such as the voltage, current, SOC (State Of Charge), and SOH (State Of Health) of the battery pack 20 from the battery pack 11, and controls the PCU 12 to control the driving of the motor 13 and the charging and discharging of the battery pack 11.

[0021] 2 is a diagram illustrating a schematic configuration of a battery pack 11. The battery pack 11 includes a battery pack 20, a plurality of battery monitoring devices 30, a battery control device 40, and a housing 50 that houses them, and corresponds to a battery monitoring system in this embodiment.

[0022] The battery pack 20 includes a series connection of a plurality of battery blocks 21. The battery blocks 21 may also be referred to as a battery stack or a battery module. Each battery block 21 includes a plurality of battery cells 22. Each battery cell 22 is composed of a lithium ion secondary battery, a nickel-hydrogen secondary battery, or the like. The lithium ion secondary battery is a secondary battery that uses lithium as a charge carrier, and may include a general lithium ion secondary battery with a liquid electrolyte as well as a so-called all-solid-state battery that uses a solid electrolyte. The battery pack 20 may include a plurality of series connections of a plurality of battery blocks 21, and each series connection may be connected in parallel. The battery pack 20 is also connected to the PCU 12 via a switch SW (e.g., a relay) and wiring 16.

[0023] The battery monitoring device 30 is also called a satellite battery module (SBM) and is provided for each battery block 21. As shown in FIG. 2, each battery monitoring device 30 includes a monitoring IC 31 as a monitoring unit, a child device side wireless IC 32 as a wireless control unit, and a child device side antenna 33 as a wireless antenna. The child device side wireless IC 32 and the child device side antenna 33 correspond to a "child device side communication unit" of the battery monitoring device 30 for communicating with the battery control device 40. The monitoring IC 31 is also called a cell supervising circuit (CSC), and acquires battery information from each battery cell 22 constituting the battery block 21 or a sensor (not shown). The battery information includes, for example, voltage information, temperature information, and current information of each battery cell 22. The monitoring IC 31 also performs self-diagnosis and generates self-diagnosis information. The self-diagnosis information is, for example, information on the operation check of the battery monitoring device 30, that is, information on abnormalities and failures of the battery monitoring device 30. Specifically, the information is information regarding confirmation of the operation of the monitoring IC 31 and the child device side wireless IC 32 that constitute the battery monitoring device 30.

[0024] The slave side wireless IC 32 is connected to the monitoring IC 31 by wire and includes a wireless MCU (Micro Control Unit) and an RF device (radio frequency device module). The slave side wireless IC 32 wirelessly transmits data received from the monitoring IC 31 via the slave side antenna 33. The slave side wireless IC 32 also transmits data received via the slave side antenna 33 to the monitoring IC 31.

[0025] The monitoring IC 31 includes a slave side storage unit 34. The slave side storage unit 34 is a non-transient substantial recording medium other than a ROM (for example, a non-volatile memory other than a ROM). The monitoring IC 31 stores the acquired battery information and self-diagnosis information in the slave side storage unit 34.

[0026] The battery control device 40 is also called a battery ECU or BMU (Battery Management Unit). The battery control device 40 is configured to be able to wirelessly communicate with each battery monitoring device 30. In detail, the battery control device 40 includes a battery control MCU 41 as a battery control unit, a parent device side wireless IC 42 as a wireless control unit, and a parent device side antenna 43 as a wireless antenna. The parent device side wireless IC 42 and the parent device side antenna 43 correspond to a "parent device side communication unit" of the battery control device 40 for communicating with the battery monitoring device 30. The battery control MCU 41 is configured by a microcomputer including a CPU, a ROM, a RAM, an input / output interface, and the like. The CPU of the battery control MCU 41 expands a program stored in the ROM into the RAM and executes it. The program stored in the ROM describes processing related to battery control.

[0027] As an example of main processing, the battery control MCU 41 instructs the battery monitoring device 30 to obtain and transmit battery information. The battery control MCU 41 also monitors the assembled battery 20, the battery block 21, and the battery cells 22 based on the battery information received from the battery monitoring device 30. The battery control MCU 41 also controls the switch SW that switches between the energized and de-energized states of the assembled battery 20 and the PCU 12 and the motor 13 based on the monitoring results, etc. The battery control MCU 41 may also transmit an equalization signal to equalize the voltages of the battery cells 22.

[0028] The master side wireless IC 42 is connected to the battery control MCU 41 by wire, and has a wireless MCU and an RF device, similar to the slave side wireless IC 32. The master side wireless IC 42 wirelessly transmits data received from the battery control MCU 41 via the master side antenna 43. The master side wireless IC 42 also transmits data received via the master side antenna 43 to the battery control MCU 41. Note that, for example, a dipole antenna, a Yagi antenna, a slot antenna, an inverted F antenna, an inverted L antenna, a chip antenna, or a zero-order antenna (for example, a zero-order resonant antenna) can be used as the master side antenna 43 and the slave side antenna 33.

[0029] The battery control MCU 41 includes a parent device storage unit 44. The parent device storage unit 44 is a non-transient substantial recording medium other than a ROM (for example, a non-volatile memory other than a ROM).

[0030] The battery monitoring system is constituted by components including a battery pack 20, a battery monitoring device 30, a battery control device 40, and a housing 50 that houses these components.

[0031] Next, the arrangement of the housing 50 and the battery block 21 and the like within the housing 50 will be described with reference to Figures 3 and 4. Figure 4 is a cross-sectional view taken along line 4-4 in Figure 3. For the sake of convenience, hatching indicating a cross section has been omitted for some of the configuration shown in Figure 4.

[0032] The housing 50 includes a bottom plate 51 and a wall portion formed along the periphery of the bottom plate 51. The bottom plate 51 has a rectangular shape, specifically, a rectangular shape. The wall portion includes a pair of first walls 52 extending in the short direction of the bottom plate 51 and a pair of second walls 53 extending in the long direction of the bottom plate 51.

[0033] The housing 50 is provided with a cover 54. The cover 54 covers the first wall portion 52 and the second wall portion 53 from above. The cover 54 is removable from a base portion consisting of the bottom plate portion 51 and the walls. The cover 54 is fixed to the base portion by a fastening member such as a bolt. The inner surfaces of the bottom plate portion 51, the first wall portion 52, the second wall portion 53, and the cover 54 form a storage portion 55. The storage portion 55 has a continuous space that stores the battery block 21, the battery monitoring device 30, and the battery control device 40 in a predetermined arrangement.

[0034] In this embodiment, the bottom plate portion 51, the first wall portion 52, the second wall portion 53, and the cover 54 are configured to have an electromagnetic shielding effect that blocks or absorbs radio waves. For example, the configuration has an electromagnetic shielding effect by being made of a metal material (e.g., aluminum).

[0035] In this embodiment, the housing 50 is mounted on the vehicle 10 so that the longitudinal direction of the rectangular parallelepiped housing 50 is the vehicle length direction of the vehicle 10. Figures 3 and 4 and the like show that the longitudinal direction of the housing 50 (the vehicle length direction of the vehicle 10) is the X direction, the short side direction of the housing 50 (the vehicle width direction of the vehicle 10) is the Y direction, and the height direction of the housing 50 is the Z direction. For example, the lower surface of the bottom plate portion 51 is the installation surface with respect to the body of the vehicle 10.

[0036] Each battery block 21 has a rectangular parallelepiped shape and is configured as a series connection of multiple battery cells 22. In this embodiment, the battery cells 22 have a flattened rectangular parallelepiped shape. The multiple battery cells 22 are stacked side by side in the short side direction of the housing 50, as shown in FIG. 5(A). In each battery block 21, the multiple battery cells 22 may be stacked side by side in the long side direction of the housing 50, as shown in FIG. 5(B). Furthermore, the multiple battery cells 22 constituting each battery block 21 may be connected in parallel to each other.

[0037] As shown in Fig. 3 and Fig. 4, the battery blocks 21 are arranged on the bottom plate portion 51 so that their longitudinal direction coincides with the lateral direction of the housing 50. In this embodiment, for convenience, it is assumed that four battery blocks 21 are housed in the housing 50. Therefore, four battery monitoring devices 30 are also housed in the housing 50. Hereinafter, the battery blocks 21 may be referred to as first to fourth battery blocks 21A to 21D, and the battery monitoring devices 30 may be referred to as first to fourth battery monitoring devices 30A to 30D. In each battery block 21, the positive and negative terminals of adjacent battery cells 22 are electrically connected by a bus bar.

[0038] In the housing section 55, a junction box 15 is disposed on the bottom plate section 51. The junction box 15 has a rectangular parallelepiped shape and accommodates a switch SW. The junction box 15 is disposed next to the first battery block 21A such that the longitudinal direction of the junction box 15 is parallel to the longitudinal direction of the battery block 21. The height dimension of the junction box 15 is smaller than the height dimension of the battery block 21.

[0039] A battery control device 40 is disposed on the upper surface of the junction box 15. A battery monitoring device 30 is disposed on the upper surface of each battery block 21. In the housing section 55, the battery control device 40 is disposed at a lower position than the battery monitoring devices 30.

[0040] In this embodiment, the first battery monitoring device 30A monitors the first battery block 21A, and the second battery monitoring device 30B monitors the second battery block 21B. The third battery monitoring device 30C monitors the third battery block 21C, and the fourth battery monitoring device 30D monitors the fourth battery block 21D.

[0041] The first to fourth battery monitoring devices 30A to 30D store unique identification information assigned to them in the child device side storage unit 34. When transmitting battery information to the battery control device 40, the first to fourth battery monitoring devices 30A to 30D also transmit the identification information assigned to them. This allows the battery control device 40 to determine which battery monitoring device transmitted the battery information.

[0042] 6, the child-side antenna 33 of each battery monitoring device 30 is configured so that the radio wave directivity can be selected from a plurality of radio wave directivities whose center directions are different. The child-side antenna 33 of this embodiment is configured so that the radio wave directivity can be selected from two radio wave directivities A and B. This configuration is for setting the radio wave directivity optimal for the battery control device 40 in each child-side antenna 33.

[0043] The reason for switching the radio wave directivity will be described with reference to FIG. 7. FIG. 7 shows the reception power of a radio signal by the parent-side antenna 43 when the radio signal is transmitted from the child-side antenna 33 of the first battery monitoring device 30A to the parent-side antenna 43 of the battery control device 40. The horizontal axis of FIG. 7 shows the channel used for wireless communication, and the larger the channel, the higher the frequency. The frequency range defined by one channel is the range of "fc-Δf / 2" to "fc+Δf / 2" defined by the frequency median value fc of this channel and the channel width Δf. Of two adjacent channels, the high frequency side of the frequency range of the low frequency channel and the low frequency side of the frequency range of the high frequency channel may overlap.

[0044] 7 is a threshold value indicating the lower limit of the received power at which accurate information can be transmitted between the battery monitoring device 30 and the battery control device 40. When the received power of the parent device side antenna 43 falls below the received power lower limit Wmin, accurate information cannot be transmitted between the battery monitoring device 30 and the battery control device 40.

[0045] When radio wave directivity A is selected as the radio wave directivity of the slave side antenna 33, among the available channels from the minimum channel (0ch) to the maximum channel (Nch), there is a channel in which the reception power of the master side antenna 43 falls below the lower limit value Wmin of reception power. The reason for this will be explained below.

[0046] As shown in Fig. 8, when a transmitting antenna AT and a receiving antenna AR are arranged in a housing made of a metal wall, when a wireless signal is transmitted from the transmitting antenna AT, the transmitted signal is diffusely reflected in the housing. As a result, a main wave, which is a signal transmitted from the transmitting antenna AT and not reflected, interferes with a reflected wave, which is a signal transmitted from the transmitting antenna AT and then reflected, and as shown in Fig. 9, the amplitude of the signal after interference becomes excessively small. As a result, there exists a channel in which the reception power of the parent device side antenna 43 falls below the reception power lower limit value Wmin. In the example shown in Fig. 9, the phase difference between the reflected wave and the main wave is about 180 degrees, and the reception power of the receiving antenna AR is excessively reduced.

[0047] 7, when the radio wave directivity of the slave side antenna 33 is switched from radio wave directivity A to radio wave directivity B, the reception power of the master side antenna 43 becomes equal to or greater than the reception power lower limit Wmin in the channel where the reception power of the master side antenna 43 was below the reception power lower limit Wmin. Also, when the radio wave directivity is switched to B, the channel where the reception power of the master side antenna 43 is below the reception power lower limit Wmin becomes a different channel from the channel when radio wave directivity A is selected.

[0048] In this way, even if accurate information cannot be transmitted between the battery monitoring device 30 and the battery control device 40 on a certain channel, by changing the radio wave directivity of the antenna, the received power can be made to be equal to or greater than the lower limit Wmin of the received power, making it possible to transmit accurate information between the battery monitoring device 30 and the battery control device 40.

[0049] Therefore, in this embodiment, in the manufacturing process of the battery pack 11, the frequency characteristics of the received power (e.g., RSSI) of the battery control device 40 when wirelessly transmitted from each battery monitoring device 30 are measured for each of the radio wave directivities A and B. Then, based on the measured frequency characteristics, as shown in Fig. 10, it is identified for each channel which of the radio wave directivities A and B of each child device side antenna 33 maximizes the received power of the parent device side antenna 43 when wireless communication is performed.

[0050] 11 is a flowchart of a process for generating map information linking each channel with the radio wave directivity that maximizes the receiving power of the parent device antenna 43. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30 during the manufacturing process of the battery pack 11.

[0051] In step S10, in any one of the battery monitoring devices 30A to 30D, the monitoring IC 31 transmits a wireless signal when radio wave directivity A is selected from the slave side storage unit 34. Here, it is assumed that the first battery monitoring device 30A is selected. The wireless signal contains identification information of the battery monitoring device 30 that is the transmission source.

[0052] In step S11, the transmitted wireless signal is received by the parent-side antenna 43. The battery control MCU 41 of the battery control device 40 calculates, based on the received signal, the frequency characteristics of the received power, which is information on the received power of the parent-side antenna 43 linked to each channel. In step S12, the battery control MCU 41 links the calculated frequency characteristics, radio wave directivity A, and identification information of the first battery monitoring device 30A that is the source of the wireless signal.

[0053] In step S13, the battery control MCU 41 determines whether or not the measurement of the received power corresponding to the radio wave directivities A and B has been completed for the first battery monitoring device 30A. If the battery control MCU 41 determines that the measurement has not been completed, the process proceeds to step S14, where the battery control MCU 41 switches the radio wave directivity of the child device side antenna 33 of the first battery monitoring device 30A from radio wave directivity A to radio wave directivity B. Thereafter, the calculated frequency characteristics, radio wave directivity B, and identification information of the first battery monitoring device 30A are linked by the processes of steps S10 to S12.

[0054] If the battery control MCU 41 determines in step S13 that the measurement is completed, the process proceeds to step S15, where it determines whether or not the measurement of the received power corresponding to the radio wave directivities A and B is completed for all the battery monitoring devices 30A-30D. If the battery control MCU 41 determines that the measurement is not completed, the process proceeds to step S16, where it switches the battery monitoring device that is the source of the wireless signal from the first battery monitoring device 30A to the second battery monitoring device 30B. Thereafter, the calculated frequency characteristics, radio wave directivities, and identification information are associated with each of the second to fourth battery monitoring devices 30B-30D through the processes of steps S10-S16.

[0055] In step S17, the battery control MCU 41 generates map information (corresponding to "directivity information") linking each channel, the radio wave directivity at which the reception power of the parent unit side antenna 43 is maximum in each channel, and the identification information of the battery monitoring device 30 based on the linking information obtained by the processing of steps S10 to S16. Taking the first battery monitoring device 30A as an example, the map information includes information that the radio wave directivity of the child unit side antenna 33 of the first battery monitoring device 30A when the reception power of the parent unit side antenna 43 is maximum in each channel that can be used for wireless communication with the first battery monitoring device 30A is radio wave directivity A or radio wave directivity B. For example, the map information includes information that the radio wave directivity at which the reception power is maximum in a channel with a frequency median of 2.40 GHz is radio wave directivity B, and information that the radio wave directivity at which the reception power is maximum in a channel with a frequency median of 2.42 GHz is radio wave directivity A.

[0056] The battery control MCU 41 stores the generated map information in the parent device side storage unit 44 .

[0057] In step S18, the battery control MCU 41 transmits the generated map information to the first to fourth battery monitoring devices 30A to 30D from the parent device side antenna 43. In this case, the radio wave directivity of each child device side antenna 33 may be set to the radio wave directivity defined in the map information in the channel used to transmit the map information.

[0058] In step S19, in each of the battery monitoring devices 30A to 30D, the monitoring IC 31 stores the map information received by the slave unit side antenna 33 in the slave unit side storage unit .

[0059] According to the present embodiment described above, it is possible to identify the radio wave directivity with the highest received power, that is, the radio wave directivity with the highest communication quality. In addition, after the battery pack 11 is shipped from the manufacturing factory, for example, it is not necessary to frequently generate map information.

[0060] Regardless of whether the radio wave directivity of the slave side antenna 33 is set to radio wave directivity A or B, there may be some channels whose reception power of the master side antenna 43 falls below the reception power lower limit Wmin. In this case, the map information may include information that prohibits the use of channels whose reception power falls below the reception power lower limit Wmin in wireless communication.

[0061] The map information may be generated in advance when the battery pack 11 is designed, rather than during the manufacturing process of the battery pack 11. In this case, during the manufacturing process of the battery pack 11, a writing device provided on the production line may store the map information generated in advance in the parent unit side storage unit 44 and the child unit side storage unit 34. The received power for generating this map information may be measured, for example, as follows.

[0062] An external measuring device is electrically connected to the battery control device 40 (specifically, for example, the parent device side antenna 43) and the battery monitoring device 30 (specifically, for example, the child device side antenna 33). In this connected state, the measuring device calculates the frequency characteristics of the received power of the parent device side antenna 43 when a wireless signal is output individually from each battery monitoring device 30. In detail, the measuring device measures the loss power (for example, the transmission characteristics) when a radio wave is propagated from the child device side antenna 33 to the parent device side antenna 43. The measuring device calculates the frequency characteristics of the received power of the parent device side memory unit 44 by adding the transmission power from the child device side antenna 33 and the loss power in the parent device side wireless IC 42, the parent device side antenna 43, the child device side wireless IC 32, the child device side antenna 33, etc. to the measured loss power.

[0063] Prior to wireless communication with the battery control device 40, each battery monitoring device 30 determines, based on the map information, whether to set the radio wave directivity of its own child device side antenna 33 to radio wave directivity A or B. The channel used in the wireless communication between the battery monitoring device 30 and the battery control device 40 may be set individually for each of the battery monitoring devices 30A to 30D, or may be set to a common channel.

[0064] The radio wave directivity switching process executed by the monitoring IC 31 of each battery monitoring device 30 will be described with reference to FIG.

[0065] In step S20, map information is read from the child device side storage unit .

[0066] In step S21, the read map information is referenced and either radio wave directivity A or B is selected as the radio wave directivity in the channel used in wireless communication with the battery control device 40.

[0067] In step S22, the radio wave directivity of the child device side antenna 33 is switched to the radio wave directivity associated with the channel used in the wireless communication, that is, the radio wave directivity selected in step S21.

[0068] Next, three examples of the child device side antenna that can change the direction of the center of radio wave directivity will be described with reference to Figs.

[0069] 13 shows a first child device side antenna 33. The first example is configured to include a plurality of antenna members having different directions of the center of radio wave directivity, and to switch between the antenna members to be used.

[0070] The slave device side antenna 33 includes a circuit board 61, a baseband IC 62 provided on the surface of the circuit board 61, a changeover switch 63, a plurality of types of antenna members, and a power feeder that electrically connects the plurality of types of antenna members and the changeover switch 63. In Fig. 13, a first antenna member 64A and a second antenna member 64B are shown as the antenna members, and a first power feeder line 65A and a second power feeder line 65B are shown as the power feeder line.

[0071] The baseband IC 62 communicates with the monitoring IC 31 via the slave-side wireless IC 32. The baseband IC 62 is connected to a first power feed line 65A or a second power feed line 65B by a changeover switch 63. As shown in FIG. 13(A), when the baseband IC 62 and the first power feed line 65A are connected by the changeover switch 63, a first antenna member 64A is used. In this case, the radio wave directivity is radio wave directivity A. On the other hand, as shown in FIG. 13(B), when the baseband IC 62 and the second power feed line 65B are connected by the changeover switch 63, a second antenna member 64B is used. In this case, the radio wave directivity is radio wave directivity B.

[0072] 14 shows a second child device side antenna 33. In the second example, the baseband ICs 62 are individually connected to the respective power feed lines, and the baseband ICs 62 to be operated are switched.

[0073] The slave device side antenna 33 includes a circuit board 61, a plurality of baseband ICs 62 provided on the surface of the circuit board 61, a changeover switch 63, a plurality of types of antenna members, and a power feeder that electrically connects the plurality of types of antenna members and the baseband IC 62. In Fig. 14, a first antenna member 64A and a second antenna member 64B are shown as the antenna members, and a first power feeder line 66A and a second power feeder line 66B are shown as the power feeder line.

[0074] 15 shows a third child device side antenna 33. The third example is a configuration in which the radio wave directivity is changed by changing the power supply point for the antenna member.

[0075] The child device side antenna 33 includes a circuit board 61, a baseband IC 62, a changeover switch 63, an antenna member 67, and first to fourth power feeders 68A to 68D. The antenna member 67 and the first to fourth power feeders 68A to 68D are provided on the plate surface of the circuit board 61. The antenna member 67 is a zero-order resonant antenna, for example a patch antenna.

[0076] In the configuration shown in Fig. 15, the radio wave directivity can be changed to four different patterns, two of which will be described below. As shown in Fig. 15(A), when the baseband IC 62 and the first feeder line 68A are connected by the changeover switch 63, the radio wave directivity in the antenna member 67 becomes radio wave directivity A. On the other hand, as shown in Fig. 15(B), when the baseband IC 62 and the fourth feeder line 68D are connected by the changeover switch 63, the radio wave directivity in the antenna member 67 becomes radio wave directivity B.

[0077] Here, the power feed lines 68A to 68D are provided in parallel on the plate surface of the circuit board 61. On the plate surface of the circuit board 61, conductive ground patterns shown by hatching are provided between adjacent power feed lines among the power feed lines 68A to 68D. The ground patterns are, for example, the ground of the baseband IC 62. In the example shown in FIG. 15, a first ground pattern 69A is provided between the first power feed line 68A and the second power feed line 68B, a second ground pattern 69B is provided between the second power feed line 68B and the third power feed line 68C, and a third ground pattern 69C is provided between the third power feed line 68C and the fourth power feed line 68D.

[0078] The ground pattern is provided to set the radio wave directivity of the child device side antenna 33 to a target radio wave directivity. In the comparative example shown in FIG. 16, no ground pattern is provided. In this case, a situation in which a current flows through the first feeder 68A will be described as an example. Capacitive coupling occurs between the first feeder 68A and the second feeder 68B. In this case, a part of the current flowing through the first feeder 68A flows through the second feeder 68B. As a result, the actual radio wave directivity of the child device side antenna 33 deviates from the target radio wave directivity.

[0079] In contrast, the configuration in which the ground pattern shown in Fig. 15 is provided can suppress the occurrence of capacitive coupling between adjacent power feed lines, thereby suppressing the occurrence of a situation in which the radio wave directivity deviates from the target radio wave directivity.

[0080] Incidentally, the power feed line connected to the zero-order resonant antenna may be provided in a different layer in the multilayer substrate. The multilayer substrate 70 shown in FIG. 17 includes a pair of surface layers, a first layer 71A and a second layer 71B, and an intermediate layer 71C sandwiched between the pair of surface layers. The first layer 71A includes a first power feed line 74A corresponding to the first power feed line 68A in FIG. 15, and a third power feed line 74C corresponding to the third power feed line 68C. Between the second layer 71B and the intermediate layer 71C, a second power feed line 74B corresponding to the second power feed line 68B, and a fourth power feed line 74D corresponding to the fourth power feed line 68D are provided. An insulating layer 73 having electrical insulation properties is provided between the second layer 71B and the intermediate layer 71C, except for the second power feed line 74B and the fourth power feed line 74D.

[0081] In the first layer 71A, a ground pattern 75 is provided between the first power feed line 74A and the third power feed line 74C. In addition, a conductive ground pattern 72 is provided between the first layer 71A and the intermediate layer 71C. Even with this configuration, deviation in radio wave directivity can be suppressed.

[0082] Next, we will explain the advantages of a configuration that can switch radio wave directivity using two examples. The first example is an example of reuse of a battery block 21 constituting a battery pack 11. The battery pack 11 of this embodiment is mounted on a vehicle 10. The battery block 21 constituting the battery pack 11 can be reused for another purpose after being used for an in-vehicle purpose. In the example shown in FIG. 18, the battery block 21 is reused from an in-vehicle purpose to a stationary equipment purpose. In a housing 81 constituting a battery pack 80 for a stationary equipment, the arrangement of each battery block 21, each battery monitoring device 30, battery control device 40, and junction box 15 is different from the arrangement for an in-vehicle purpose. In addition, the shape of the housing 81 for a stationary equipment purpose is different from the shape of the housing 50 for an in-vehicle purpose.

[0083] Fig. 19 shows the frequency characteristics of the received power based on the map information generated by the processing of Fig. 11 when the battery pack 11 is used for in-vehicle applications. In the example shown in Fig. 19, the radio wave directivity at which the received power is maximum is linked to each channel.

[0084] On the other hand, FIG. 20 shows frequency characteristics when the radio wave directivity of each channel is set based on the map information used for vehicle-mounted applications when a battery pack 80 including a battery block 21 reused for stationary equipment applications is used. Even if the received power of each channel is equal to or greater than the lower limit Wmin in the case of vehicle-mounted applications, if the application changes and the shape of the housing 81 or the arrangement state within the housing 81 changes, the radio wave propagation path between the slave side antenna 33 and the master side antenna 43 within the housing 81 changes significantly, and there will be a channel where the received power is below the lower limit Wmin. In this way, when the battery is reused, at least one of the radio wave propagation path within the housing, the arrangement of the antenna, and the radio wave directivity of the antenna is not optimized, and communication quality is reduced. As a result, for example, the antenna needs to be replaced when reused.

[0085] Here, even if the battery is reused and its use is changed, by executing the process of Fig. 11, it is possible to set radio wave directivity that can make the reception power of the parent unit antenna 43 equal to or greater than the reception power lower limit value Wmin in each channel, as shown in Fig. 21. After the battery pack 80 is manufactured by packing each battery block 21 to be reused, the battery monitoring device 30 and the battery control device 40 provided in each battery block 21, etc., into a reuse destination housing 81, the process of Fig. 11 may be executed when the battery control device 40 of the battery pack 80 is started for the first time.

[0086] In this way, according to this embodiment, accurate information can be exchanged between the battery control device 40 and the battery monitoring device 30 via wireless communication, without depending on the shape of the housing at the reuse destination or the arrangement of the components contained within the housing, and without replacing the child unit antenna or the parent unit antenna when reusing.

[0087] The second example is a case where the battery pack 11 is installed in the vehicle 10 after shipment of the battery pack 11. Components of the battery pack 11, such as the battery monitoring device 30, may fail. In addition, radio waves from a portable terminal used by an occupant of the vehicle 10 inside the vehicle may become noise, and the communication environment in which the vehicle 10 is placed may change. In this case, as shown in FIG. 22, some of the channels may become unusable, and the received power in the usable channels may fall below the received power lower limit value Wmin. Even in this case, by switching the radio wave directivity of the slave side antenna 33, the received power in the usable channels can be made equal to or higher than the received power lower limit value Wmin, as shown in FIG. 23.

[0088] 24 is a flowchart showing the procedure of the radio wave directivity switching process corresponding to the second example. This process is executed by the battery control MCU 41.

[0089] In step S30, it is determined whether or not any of the channels used for wireless communication with each battery monitoring device 30 is unavailable.

[0090] If it is determined in step S30 that there is an unavailable channel, the process proceeds to step S31, where it is determined whether or not the reception power of the parent device antenna 43 in the available channel is below the lower limit Wmin of reception power.

[0091] If it is determined in step S31 that the received power is greater than or equal to the lower limit Wmin of the received power, or if it is determined in step S30 that there are no unavailable channels, the process proceeds to step S32, where wireless communication between the battery control device 40 and each battery monitoring device 30 is permitted.

[0092] On the other hand, if it is determined in step S31 that the received power is below the lower limit Wmin of the received power, the process proceeds to step S33, where the radio wave directivity is switched. For example, if the current radio wave directivity is set to radio wave directivity A, it is switched to radio wave directivity B.

[0093] In step S34, after switching of the radio wave directivity, the wireless signal transmitted from the battery monitoring device 30 is received by the parent device antenna 43 and the received power is measured. Then, based on the received power, it is determined whether the received power of the parent device antenna 43 in the available channel is equal to or greater than the received power lower limit value Wmin.

[0094] If it is determined in step S34 that the received power is equal to or greater than the lower limit Wmin of the received power, the process proceeds to step S32. On the other hand, if it is determined in step S34 that the received power is below the lower limit Wmin of the received power, the process proceeds to step S35, where it is determined that wireless communication is impossible. Then, the occurrence of an abnormality is notified to the upper control device.

[0095] In this way, according to this embodiment, even if the wireless communication environment deteriorates, for example, it is possible to improve the robustness of wireless communication.

[0096] <Modification of the first embodiment> The arrangement of the battery control device 40 and the battery monitoring devices 30 in the storage section 55 of the housing 50 is not limited to the arrangement shown in Figures 3 and 4. For example, as shown in Figure 25, the battery control device 40 may be attached to the top surface of the battery block 21, and the battery monitoring devices may be attached to each side surface of the battery block 21. Note that Figure 25 illustrates the battery block 21 etc. in a simplified manner compared to Figure 3.

[0097] Some of the components of the bottom plate 51, the first wall 52, the second wall 53, and the cover 54 may not have an electromagnetic shielding effect. For example, the components are made of synthetic resin, which results in no electromagnetic shielding effect.

[0098] The child device side antenna may be configured to be selectable from three or more radio wave directivities with different directions of the center of radio wave directivity. In this case, it is sufficient that the radio wave directivities are set to a radio wave directivity other than the radio wave directivity at which the parent device side antenna 43 has the smallest received power when wireless transmission is performed in the channel used for wireless communication between the parent device side antenna and the child device side antenna. Also, the radio wave directivity is not limited to the radio wave directivity at which the parent device side antenna 43 has the largest received power, but may be set to a radio wave directivity other than the radio wave directivity at which the received power is the smallest and the largest. Also, when there are multiple radio wave directivities at which the received power is equal to or greater than the lower limit Wmin of the received power in a certain channel, map information may be generated to set multiple radio wave directivities available in that channel.

[0099] <Second embodiment> The second embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, instead of the child unit side antenna 33, the parent unit side antenna 43 provided in the battery control device 40 is configured to be able to change its radio wave directivity. This allows the parent unit side antenna 43 to set an optimal radio wave directivity for each battery monitoring device 30. In this embodiment, the parent unit side antenna 43 is configured to be able to switch its radio wave directivity to either radio wave directivity A or B, with the configuration shown in Figs. 13 to 15 and the like.

[0100] 26 is a flowchart of a process for generating map information linking each channel with the radio wave directivity that maximizes the receiving power of the parent device antenna 43. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30 during the manufacturing process of the battery pack 11.

[0101] In step S40, in each of the battery monitoring devices 30A to 30D, the monitoring IC 31 transmits a wireless signal from the slave-side storage unit 34. The wireless signal contains identification information of the transmitting battery monitoring device 30. The transmission periods of the wireless signals of each of the battery monitoring devices 30A to 30D are set so as not to overlap, for example.

[0102] In step S41, the transmitted wireless signal is received by the parent unit side antenna 43 set to radio wave directivity A. The battery control MCU 41 calculates the frequency characteristics of the received power of the parent unit side antenna 43 for each of the battery monitoring devices 30A-30D based on the received signal. In step S42, the battery control MCU 41 associates the calculated frequency characteristics of the received power corresponding to each of the battery monitoring devices 30A-30D with the radio wave directivity A.

[0103] In step S43, the battery control MCU 41 determines whether or not the measurement of the received power corresponding to the parent unit side radio wave directivities A and B has been completed. If the battery control MCU 41 determines that the measurement has not been completed, the process proceeds to step S44, where the battery control MCU 41 switches the radio wave directivity of the parent unit side antenna 43 from radio wave directivity A to radio wave directivity B. Thereafter, the calculated frequency characteristics of the received power corresponding to each of the battery monitoring devices 30A-30D are associated with the radio wave directivity B through the processes of steps S40-S42.

[0104] If the battery control MCU 41 determines in step S43 that the process is completed, the process proceeds to step S45, where the battery control MCU 41 generates map information (corresponding to "directivity information") that links each channel with the radio wave directivity that maximizes the reception power of the parent device side antenna 43 for each channel, based on the linking information obtained by the processes in steps S40 to S44. The battery control MCU 41 stores the generated map information in the parent device side storage unit 44.

[0105] The map information may be generated in advance at the time of designing the battery pack 11, rather than during the manufacturing process of the battery pack 11. In this case, during the manufacturing process of the battery pack 11, the map information generated in advance may be stored in the parent device storage unit 44 by a writing device provided on the production line.

[0106] The radio wave directivity switching process executed by the battery control MCU 41 of the battery control device 40 will be described with reference to FIG.

[0107] In step S50, map information is read from the parent device storage unit 44. In step S51, the read map information is referenced and either radio wave directivity A or B is selected as the radio wave directivity in the channel used in wireless communication with the battery control device 40.

[0108] In step S52, the radio wave directivity of the parent device antenna 43 is switched to the radio wave directivity associated with the channel used in the wireless communication, that is, the radio wave directivity selected in step S51.

[0109] According to the present embodiment described above, proper wireless communication can be performed between the battery control device 40 and each battery monitoring device 30.

[0110] <Modification of the second embodiment> Instead of the reception power of the parent-side antenna 43, map information may be generated that links each channel to the radio wave directivity at which the reception power of the child-side antenna 33 is maximized in each channel. This map information is generated individually by linking it to each battery monitoring device 30 (each child-side antenna 33). The method of generating the map information will be described below. The battery control device 40 transmits a radio signal from the parent-side antenna 43 set to radio wave directivity A to each child-side antenna 33. In each battery monitoring device 30A to 30D, the monitoring IC 31 calculates the frequency characteristic of the reception power of the child-side antenna 33 based on the reception signal of the child-side antenna 33, and links the calculated frequency characteristic of the reception power to the radio wave directivity A. In each battery monitoring device 30A to 30D, the monitoring IC 31 transmits information linking the frequency characteristic and the radio wave directivity A from the child-side antenna 33 to the parent-side antenna 43. The battery control MCU 41 receives the associated information through the parent unit side antenna 43. Next, the battery control device 40 transmits a wireless signal from the parent unit side antenna 43 set to radio wave directivity B to each child unit side antenna 33. Then, similar to the case of radio wave directivity A, the battery control MCU 41 receives the information associated with the frequency characteristics and radio wave directivity B through the parent unit side antenna 43. Based on the associated information, the battery control MCU 41 generates map information that associates each channel with the radio wave directivity that maximizes the reception power of the child unit side antenna 33 for each channel. Incidentally, the calculation of the frequency characteristics and the association between the frequency characteristics and the radio wave directivity may be performed in the battery control device 40 (battery control MCU 41) instead of the battery monitoring device 30 (monitoring IC 31).

[0111] The parent-side antenna may be configured to be selectable from three or more radio wave directivities with different directions of the center of radio wave directivity. In this case, it is sufficient that the radio wave directivities are set to a radio wave directivity other than the radio wave directivity at which the parent-side antenna 43 or the child-side antenna 33 has the smallest received power when wireless transmission is performed in the channel used for wireless communication between the parent-side antenna and the child-side antenna. Also, the radio wave directivity is not limited to the radio wave directivity at which the parent-side antenna 43 or the child-side antenna 33 has the largest received power, and may be set to a radio wave directivity other than the radio wave directivity at which the received power is minimum and maximum. Also, when there are multiple radio wave directivities at which the received power is equal to or greater than the lower limit Wmin of the received power in a certain channel, map information may be generated to set multiple radio wave directivities available in that channel.

[0112] In addition to the parent unit antenna, the radio wave directivity of each child unit antenna may be changeable as in the first embodiment.

[0113] <Third embodiment> The third embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, as shown in Fig. 18, when manufacturing a battery pack 80 as a reused product, the optimal radio wave directivity of each child device side antenna 33 is specified, and the battery state history information of each battery block 21 as a reused product can be read out.

[0114] Fig. 28 shows a battery monitoring system, a mobile terminal 300 (corresponding to an "inspection device") applied to the system, and an external server 310. In Fig. 28, the same components as those shown in Fig. 2 above are denoted by the same reference numerals for convenience.

[0115] The mobile terminal 300 is a device for determining whether the battery block 21 can be reused, and is used by an operator. The mobile terminal 300 includes a control unit 301, a wireless IC 302, an antenna 303, an operation unit 304, a display unit 305, and a memory unit 306.

[0116] The control unit 301 is mainly composed of a microcomputer and performs various processes. The wireless IC 302 is connected to the control unit 301 by wire and has a wireless MCU and an RF device. The wireless IC 302 wirelessly transmits data received from the control unit 301 via the antenna 303. The wireless IC 302 also transmits data received via the antenna 303 to the control unit 301. The storage unit 306 is a non-transient substantial recording medium other than ROM (for example, a non-volatile memory other than ROM).

[0117] The operation unit 304 is operated by an operator and is connected by wire to the control unit 301. The operation unit 304 is, for example, a touch panel, a touch display, hardware keys such as a keyboard, or a pointing device such as a mouse.

[0118] The display unit 305 is connected to the control unit 301 by wire and is a device that outputs the results of processing by the control unit 301. The display unit 305 is, for example, a touch panel or a touch display. The display unit 305 displays, for example, history information of the battery state wirelessly transmitted from the battery monitoring device 30 attached to the battery block 21.

[0119] The server 310 includes a control unit 311, a communication unit 312, and a storage unit 313. The control unit 311 is mainly configured with a microcomputer, and performs various processes. The communication unit 312 is connected to the control unit 311 by wire. The communication unit 312 is capable of communicating with the mobile terminal 300 and the battery monitoring device 30 via a communication network 320. The communication network 320 is at least one of a wired network and a wireless network. The storage unit 313 is a non-transient substantial recording medium other than ROM (for example, a non-volatile memory other than ROM).

[0120] Fig. 29 is a flowchart of a process for generating map information linking each channel with the radio wave directivity at which the reception power of the parent device antenna 43 is maximized. This process is executed by the mobile terminal 300, the battery control MCU 41, and the monitoring IC 31 of each battery monitoring device 30 in the manufacturing process of the battery pack 80 as a reused product. This process is executed on the condition that the battery control device 40 and the mobile terminal 300 are connected so as to be capable of communication (wireless communication or wired communication). In Fig. 29, the same processes as those shown in Fig. 11 above are denoted by the same reference numerals for convenience.

[0121] In step S60, the battery control MCU 41 determines whether or not there is a request from the mobile terminal 300 to transmit history information of the battery state. The request for history information is transmitted from the mobile terminal 300 to the battery control device 40 when an operator connects the mobile terminal 300 and the battery control MCU 41 to enable communication (wired or wireless) between them and operates the operation unit 304. When the battery control MCU 41 determines that there is a transmission request, the process proceeds to step S61, and transmits history information of the battery state stored in the parent device storage unit 44 to the mobile terminal 300. The history information includes at least one of the following (1) to (6). The information (1) to (5) is information indicating changes over time in the state of the battery block 21, and the information (6) is information independent of the usage history of the battery block 21.

[0122] (1) Temperature history information showing temperature changes over time for the battery block (2) Voltage history information showing voltage changes over time for the battery block (3) Current history information showing changes in current of the battery block over time (4) Information for determining the health of the battery block, including at least one of the SOC, SOH, remaining energy, and self-discharge rate trends of the battery block, and internal resistance. (5) Information for determining the expected life of the battery block, including at least one of the battery block's manufacturing date, start date of use, energy processing capacity, and capacity processing capacity. (6) Information on the economic business operator that markets the battery block, including at least one of the following: the manufacturer of the battery block, the model of the battery block, the place of manufacture, the date of manufacture, the rated capacity, the minimum voltage, the nominal voltage, the maximum voltage, and the operating temperature range.

[0123] This causes the battery state history information to be displayed on the display unit 305 of the mobile terminal 300. The worker can grasp the state of the battery block 21 based on this displayed information.

[0124] After the process of step S61 is completed, the processes of steps S10 to S19 are executed, whereby map information is generated that specifies the optimal radio wave directivity of each child device side antenna 33 in the battery pack 80 that is a reused item.

[0125] According to the present embodiment described above, when manufacturing the battery pack 80 as a reused product, it is possible to identify the optimal radio wave directivity of each child device side antenna 33 and to grasp the state of each battery block 21 as a reused product.

[0126] <Modification of the third embodiment> All or a part of the history information of the above information (1) to (6) may be stored in the storage unit 313 of the server 310. The history information may be periodically transmitted from the battery monitoring device 30 to the server 310 via the communication network 320, so that the history information in the storage unit 313 of the server 310 may be periodically updated. The mobile terminal 300 may receive all or a part of the information of the above information (1) to (6) from the server 310 via the communication unit 312, the communication network 320, and the wireless IC 302.

[0127] When the battery block 21 is reused, the state of each battery block 21, which is a reused item, can be grasped by transmitting information from the server 310 to the mobile terminal 300. If the server 310 has measures to prevent data tampering, such as a block chain, it is possible to obtain highly reliable history information.

[0128] Incidentally, it is preferable that the history information stored in the storage unit 313 of the server 310 is information that is updated infrequently, such as the above-mentioned information (6).

[0129] <Fourth embodiment> The fourth embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. The radio wave directivity setting process can be executed not only during the manufacturing process of the battery pack 11, but also after the vehicle 10 is delivered to the user. In this embodiment, the radio wave directivity setting process is permitted to be executed when the vehicle 10 is parked or when the battery pack 20 is being charged by the external charger CM.

[0130] Fig. 30 is a flowchart of a process for generating map information linking each channel with the radio wave directivity that maximizes the receiving power of the parent device antenna 43. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30. In Fig. 30, the same processes as those shown in Fig. 11 are denoted by the same reference numerals for convenience.

[0131] In step S70, the battery control MCU 41 determines whether or not either a first condition that the vehicle 10 is in a parked state or a second condition that the battery pack 20 mounted on the parked vehicle 10 is being charged by the external charger CM is satisfied. The process of step S70 is a process for improving the measurement accuracy of the received power of the parent unit side antenna 43.

[0132] Due to vibrations and the like that occur with the vehicle 10 traveling, the frequency characteristics of the radio signal received by the parent unit antenna 43 may change. In this case, there is a concern that the accuracy of map information that links the radio wave directivity at which the parent unit antenna 43 has the maximum reception power with each channel may decrease, or the time required to generate the map information may become longer. For this reason, it is desirable to measure the reception power in a situation where vibrations and the like do not occur. Therefore, the first condition is set. For example, when it is determined that a start switch or an ignition switch that permits the vehicle 10 to travel or instructs the vehicle to start and is operated by a user is turned off, it may be determined that the first condition is satisfied.

[0133] Even when the battery pack 20 is being charged by the external charger CM, the vehicle 10 is in a stopped state and no vibrations or the like occur. In consideration of this, the second condition is set.

[0134] When the battery control MCU 41 determines that neither the first condition nor the second condition is satisfied, the battery control MCU 41 does not execute the process of generating map information. On the other hand, when the battery control MCU 41 determines that either the first condition or the second condition is satisfied, the battery control MCU 41 proceeds to step S71 and determines whether or not a specific condition is satisfied. The specific condition is a condition for determining whether or not the radio wave propagation path between the parent unit side antenna 43 and each child unit side antenna 33 in the casing 50 has changed significantly from the radio wave propagation path in the situation where the received power was measured by the process of Fig. 11 during the manufacturing process of the battery pack 11. The specific condition can be, for example, the conditions (A) to (C) in Fig. 31.

[0135] (A) A condition that the travel distance (e.g., accumulated travel distance) of the vehicle 10 exceeds the judgment distance Lth. When the travel distance becomes long, the bolts for fixing the cover 54 to the base part of the housing 50 may loosen, and the space of the storage part 55 may change. In this case, the radio wave propagation path may change significantly, and the frequency characteristics of the reception power of the parent unit side antenna 43 may change significantly. In order to periodically execute the map information generation process, the judgment distance Lth may be increased stepwise every time the travel distance exceeds the judgment distance Lth. Moreover, the travel time (accumulated travel time) may be used instead of the travel distance.

[0136] (B) The condition that the temperature of the battery block 21 exceeds a judgment temperature. When the battery block 21 becomes hot, the radio wave propagation path may change significantly due to thermal expansion of the housing 50, etc. The judgment temperature is set to a value higher than the temperature of the battery block 21 in a situation where the received power is measured in the manufacturing process of the battery pack 11.

[0137] (C) A condition that the in-vehicle air conditioning device is operated by the user of the vehicle 10, for example, that the set temperature inside the vehicle is changed. A situation in which the user operates the air conditioning device is a situation in which the temperature around the battery pack 11 may deviate from the temperature at the time of manufacturing the battery pack 11, and the radio wave propagation path may change significantly.

[0138] When the battery control MCU 41 determines that the specific condition is met, the process of step S10 is executed. Here, the battery control MCU 41 transmits a command to transmit a wireless signal from the child device side antenna 33 from the parent device side antenna 43 to the child device side antenna 33. When the monitoring IC 31 of the battery monitoring device 30 determines that the command has been received, it transmits a wireless signal from the child device side antenna 33.

[0139] In step S11, the temperature, humidity, and air pressure of the accommodation unit 55 when measuring the received power may be detected by the detection unit, and the temperature, humidity, and air pressure may be linked to the radio wave directivity and the like in the map information.

[0140] According to the present embodiment described above, the radio wave directivity of each channel is set in accordance with changes in the radio wave propagation path, so that the quality of wireless communication between the battery monitoring device 30 and the battery control device 40 can be improved.

[0141] <Fifth embodiment> Hereinafter, the fifth embodiment will be described with reference to the drawings, focusing on the differences from the fourth embodiment. In this embodiment, the execution of the radio wave directivity setting process is permitted when the vehicle 10 is traveling.

[0142] Fig. 32 is a flowchart of a process for generating map information linking each channel with the radio wave directivity that maximizes the receiving power of the parent device antenna 43. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30. In Fig. 32, the same processes as those shown in Fig. 11 are denoted by the same reference numerals for convenience.

[0143] In step S80, the battery control MCU 41 judges whether or not a specific condition is satisfied while the vehicle 10 is traveling. The process of step S80 is a process for improving the measurement accuracy of the received power of the parent unit side antenna 43. The specific condition is a condition for judging whether or not the radio wave propagation path between the parent unit side antenna 43 and each child unit side antenna 33 has changed significantly while traveling, and is, for example, a condition for grasping that the vibration generated due to traveling has increased or the noise in the storage section 55 has increased. The specific condition is, for example, a condition that the current flowing through the battery pack 20 exceeds a judgment current, or a condition that the vibration detected by an acceleration sensor that detects the acceleration of the vehicle 10 has exceeded a judgment value.

[0144] If the battery control MCU 41 determines that the specific condition is met, the process of step S10 is executed.

[0145] According to the present embodiment described above, even if the radio wave propagation path changes while the vehicle 10 is traveling, the quality of the wireless communication between the battery monitoring device 30 and the battery control device 40 can be improved.

[0146] Sixth Embodiment Hereinafter, the sixth embodiment will be described with reference to the drawings, focusing on the differences from the fourth and fifth embodiments. In this embodiment, when an abnormality occurs in the battery pack 11, the map information is updated.

[0147] Fig. 33 shows the battery pack 11 in an abnormal state. In Fig. 33, the same components as or corresponding components to those shown in Figs. 3 and 4 are denoted by the same reference numerals for convenience. In the example shown in Fig. 33, the arrangement position of the first battery block 21A is shifted from its normal arrangement position. In this case, the radio wave propagation path between the battery control device 40 and each of the battery monitoring devices 30A-30D changes significantly, and the frequency characteristics of the received power of the parent unit side antenna 43 may significantly deviate from the frequency characteristics measured in the manufacturing process of the battery pack 11.

[0148] Therefore, in this embodiment, when it is determined that the radio wave propagation path has changed significantly, the map information is generated again and updated.

[0149] Fig. 34 is a flowchart of a process for generating map information linking each channel with the radio wave directivity that maximizes the receiving power of the parent device antenna 43. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30. In Fig. 34, the same processes as those shown in Fig. 11 are denoted by the same reference numerals for convenience.

[0150] In step S90, the battery control MCU 41 judges whether or not an abnormality has occurred in the battery pack 11 (for example, abnormal deformation of the battery pack 11). Abnormalities in the battery pack 11 include, in addition to abnormality in which the arrangement state of each battery block 21, each battery monitoring device 30, and battery control device 40 in the housing section 55 deviates from a predetermined arrangement state, detachment of the cover 54 from the base section of the housing 50, voltage abnormality of the battery cells 22 constituting the battery block 21, water intrusion into the battery block 21, detection of smoke generation in the housing section 55, and activation of an airbag device provided in the vehicle. The predetermined arrangement state is, for example, the arrangement state of each battery block 21, each battery monitoring device 30, and battery control device 40 in the housing section 55 of a mass-produced battery pack 11.

[0151] If the battery control MCU 41 determines that an abnormality has occurred, the process of step S10 is executed.

[0152] According to the present embodiment described above, even if an abnormality occurs in the battery pack 11, degradation in the quality of wireless communication between the battery monitoring device 30 and the battery control device 40 can be suppressed as much as possible.

[0153] Seventh embodiment The seventh embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, when generating map information, a communication error rate when wireless communication is performed between the parent device side antenna 43 and the child device side antenna 33 is used instead of the received power. The communication error rate is, for example, a packet error rate or a bit error rate.

[0154] In this embodiment, in the manufacturing process of the battery pack 11, when wireless transmission is performed from each battery monitoring device 30 for each of the radio wave directivities A and B, the communication error rate of each channel is measured as shown in Fig. 35. Then, based on the measured communication error rate, the radio wave directivity of each child device side antenna 33, in which the communication error rate when wireless communication is performed is equal to or less than the threshold value Eth, is specified for each channel. At this time, the radio wave directivity in which the communication error rate exceeds the threshold value Eth is not used.

[0155] In the example shown in FIG. 35, radio wave directivity A is associated with the first channel, radio wave directivity B is associated with the second channel, and radio wave directivity A and B are associated with the third channel.

[0156] 36 is a flowchart of a process for generating map information linking radio wave directivity with each channel. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30 during the manufacturing process of the battery pack 11.

[0157] In step S100, in any one of the battery monitoring devices 30A to 30D, the monitoring IC 31 transmits a wireless signal when radio wave directivity A is selected from the slave side storage unit 34. Here, it is assumed that the first battery monitoring device 30A is selected. The wireless signal contains identification information of the battery monitoring device 30 that is the transmission source.

[0158] In step S101, the transmitted wireless signal is received by the parent device antenna 43. The battery control MCU 41 measures a communication error rate based on the received signal. In step S102, the battery control MCU 41 associates the measured communication error rate, radio wave directivity A, and identification information of the first battery monitoring device 30A that is the source of the wireless signal.

[0159] In step S103, the battery control MCU 41 determines whether or not the measurement of the communication error rate corresponding to the radio wave directivities A and B has been completed for the first battery monitoring device 30A. If the battery control MCU 41 determines that the measurement has not been completed, the process proceeds to step S104, where the battery control MCU 41 switches the radio wave directivity of the child device side antenna 33 of the first battery monitoring device 30A from radio wave directivity A to radio wave directivity B. Thereafter, the measured communication error rate, radio wave directivity B, and identification information of the first battery monitoring device 30A are linked together by the processes of steps S100 to S102.

[0160] If the battery control MCU 41 determines in step S103 that the measurement is completed, the process proceeds to step S105, where it determines whether or not the measurement of the communication error rates corresponding to the radio wave directivities A and B for all the battery monitoring devices 30A-30D is completed. If the battery control MCU 41 determines that the measurement is not completed, the process proceeds to step S106, where it switches the battery monitoring device that is the source of the wireless signal from the first battery monitoring device 30A to the second battery monitoring device 30B. Thereafter, the measured communication error rate, radio wave directivity, and identification information are linked for each of the second to fourth battery monitoring devices 30B-30D by the processes of steps S100-S106.

[0161] In step S107, the battery control MCU 41 generates map information (corresponding to "directivity information") that links each channel, the radio wave directivity at which the communication error rate is equal to or lower than the threshold value Eth in each channel, and the identification information of the battery monitoring device 30 based on the linking information obtained by the processing in steps S100 to S106. The battery control MCU 41 stores the generated map information in the parent device side storage unit 44. Here, each channel may be linked to the radio wave directivity of radio wave directivity A or B at which the communication error rate is minimum.

[0162] In step S108, the battery control MCU 41 transmits the generated map information from the parent unit side antenna 43 to the first to fourth battery monitoring devices 30A to 30D. In this case, the radio wave directivity of each child unit side antenna 33 may be set to the radio wave directivity defined in the map information in the channel used for transmitting the map information. In step S109, in each of the battery monitoring devices 30A to 30D, the monitoring IC 31 stores the map information received by the child unit side antenna 33 in the child unit side memory unit 34.

[0163] According to the present embodiment described above, it is possible to obtain the same effects as those of the first embodiment. Incidentally, the configurations of the second to seventh embodiments can also be applied to this embodiment.

[0164] Eighth embodiment Hereinafter, the eighth embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, when generating map information, the difference between the received power and the noise floor is used instead of the received power.

[0165] In this embodiment, in the manufacturing process of the battery pack 11, the difference is measured when radio transmission is performed from each battery monitoring device 30 for each of the radio wave directivities A and B. Then, based on the measured difference, a radio wave directivity of the radio wave directivities A and B whose difference is equal to or greater than a threshold value Wth is identified for each channel. The larger the difference, the greater the communication tolerance against noise. For this reason, radio wave directivities whose difference is below the threshold value Wth are not used for each channel.

[0166] Fig. 37 shows the frequency characteristics of the difference between the received power and the noise floor of the parent unit antenna 43 when wireless transmission is performed with the radio wave directivity of the child unit antenna 33 set to radio wave directivity A. Fig. 38 shows the case when the radio wave directivity of the child unit antenna 33 is set to radio wave directivity B.

[0167] 37 and 38, in the first channel, the difference ΔW corresponding to the radio wave directivity A is 25 dBm, and the difference ΔW corresponding to the radio wave directivity B is 17 dBm. When the threshold value Wth is 20 dBm, the radio wave directivity A is associated with the first channel.

[0168] In the second channel, the difference ΔW corresponding to the radio wave directivity A is 23 dBm, and the difference ΔW corresponding to the radio wave directivity B is 25 dBm. Therefore, the radio wave directivities A and B are linked in the second channel.

[0169] In the third channel, the difference ΔW corresponding to the radio wave directivity A is 15 dBm, and the difference ΔW corresponding to the radio wave directivity B is 30 dBm. Therefore, the radio wave directivity B is associated with the third channel.

[0170] 39 is a flowchart of a process for generating map information linking radio wave directivity with each channel. This process is executed by the battery control MCU 41 of the battery control device 40 and the monitoring IC 31 of each battery monitoring device 30 during the manufacturing process of the battery pack 11.

[0171] In step S120, in any one of the battery monitoring devices 30A to 30D, the monitoring IC 31 transmits a wireless signal when radio wave directivity A is selected from the slave side storage unit 34. Here, it is assumed that the first battery monitoring device 30A is selected. The wireless signal contains identification information of the battery monitoring device 30 that is the transmission source.

[0172] In step S121, the transmitted wireless signal is received by the parent unit antenna 43. The battery control MCU 41 measures the difference ΔW between the received power and the noise floor based on the received signal. Information on the noise floor used to measure the difference ΔW may be stored in advance in the parent unit storage unit 44, for example. In step S122, the battery control MCU 41 links the measured difference ΔW, the radio wave directivity A, and the identification information of the first battery monitoring device 30A that is the source of the wireless signal.

[0173] In step S123, the battery control MCU 41 determines whether or not measurement of the difference ΔW corresponding to the radio wave directivities A and B has been completed for the first battery monitoring device 30A. If the battery control MCU 41 determines that measurement has not been completed, the process proceeds to step S124, where the battery control MCU 41 switches the radio wave directivity of the child device side antenna 33 of the first battery monitoring device 30A from radio wave directivity A to radio wave directivity B. Thereafter, the measured difference ΔW, radio wave directivity B, and identification information of the first battery monitoring device 30A are linked together by the processes of steps S120 to S122.

[0174] If the battery control MCU 41 determines in step S123 that the measurement is completed, the process proceeds to step S125, where it determines whether or not the measurement of the difference ΔW corresponding to the radio wave directivities A and B for all the battery monitoring devices 30A-30D is completed. If the battery control MCU 41 determines that the measurement is not completed, the process proceeds to step S126, where it switches the battery monitoring device that is the source of the wireless signal from the first battery monitoring device 30A to the second battery monitoring device 30B. Thereafter, the measured difference ΔW, radio wave directivity, and identification information are linked for each of the second to fourth battery monitoring devices 30B-30D by the processes of steps S120-S126.

[0175] In step S127, the battery control MCU 41 generates map information (corresponding to "directivity information") linking each channel with the radio wave directivity for which the difference ΔW is equal to or greater than the threshold value Wth, and the identification information of the battery monitoring device 30, based on the linking information obtained by the processing in steps S120 to S126. The battery control MCU 41 stores the generated map information in the parent device storage unit 44. Here, each channel may be linked with the radio wave directivity of radio wave directivities A and B for which the difference ΔW is maximum.

[0176] In step S128, the battery control MCU 41 transmits the generated map information from the parent unit side antenna 43 to the first to fourth battery monitoring devices 30A to 30D. In this case, the radio wave directivity of each child unit side antenna 33 may be set to the radio wave directivity defined in the map information in the channel used for transmitting the map information. In step S129, in each of the battery monitoring devices 30A to 30D, the monitoring IC 31 stores the map information received by the child unit side antenna 33 in the child unit side memory unit 34.

[0177] According to the present embodiment described above, even if the received power lower limit value Wmin differs for each channel, it is possible to improve the quality of wireless communication between the battery control device 40 and the battery monitoring device 30. Incidentally, the configurations of the second to seventh embodiments can also be applied to this embodiment.

[0178] <Ninth embodiment> The ninth embodiment will be described below with reference to Fig. 40 and Fig. 41, focusing on the differences from the above-mentioned embodiments. In Fig. 40 and Fig. 41, the same reference numerals are used for the same or corresponding configurations as those described in the above-mentioned embodiments for convenience. Fig. 41 is a cross-sectional view taken along line 41-41 in Fig. 40.

[0179] The vehicle includes a chassis 100 as a vehicle body made of a metal material, and wheels 110. The chassis 100 includes a chassis bottom plate portion 101 extending in the vehicle length direction, a side plate portion 102, a chassis top plate portion 103, and an end plate portion 104. The side plate portion 102 extends upward from an end portion of the chassis bottom plate portion 101 in the vehicle width direction. The chassis top plate portion 103 covers the side plate portion 102 from above. The end plate portion 104 covers both ends of the chassis bottom plate portion 101, the side plate portion 102, and the chassis top plate portion 103. The inner surfaces of the chassis bottom plate portion 101, the side plate portion 102, the chassis top plate portion 103, and the end plate portion 104 form a storage portion 105 that stores the battery pack 11.

[0180] The bottom plate 51 constituting the housing 50 is disposed on the chassis bottom plate 101. A space is formed between the chassis top plate 103 and the cover 54 constituting the housing 50. In this embodiment, the bottom plate 51, the first wall 52, the second wall 53 and the cover 54 are made of synthetic resin and are configured to have no electromagnetic shielding effect. Therefore, radio waves transmitted from the parent device side antenna 43 and the child device side antenna 33 pass through the housing 50. However, the radio waves are reflected by the chassis 100 made of a metal material.

[0181] Incidentally, among the bottom plate portion 51, the first wall portion 52, the second wall portion 53 and the cover 54, some of them (for example, the cover 54) may be made of synthetic resin.

[0182] In the present embodiment described above, diffuse reflection of radio waves occurs in the storage unit 105. Furthermore, the communication environment in the storage unit 105 may change due to reuse or the like. For this reason, the configurations described in the above embodiments can be applied.

[0183] Tenth embodiment Hereinafter, the tenth embodiment will be described with a focus on the differences from the ninth embodiment with reference to Fig. 42. In Fig. 42, the same components as or corresponding components to those described in the above embodiments are denoted by the same reference numerals for convenience.

[0184] The battery control device 40 is disposed outside the housing 50, in the housing portion 105. More specifically, the battery control device 40 is attached to the upper surface of the cover .

[0185] In this embodiment, the cover 54, the first wall portion 52, the second wall portion 53, and the bottom plate portion 51 are made of a metal material. In this case, in order to perform communication between the battery monitoring devices 30A to 30D housed in the housing 50 and the battery control device 40, a configuration is required that provides a communication connection between the inside and outside of the housing 50.

[0186] The battery pack 11 of the present embodiment includes a relay device 120 as a configuration for communication connection. The relay device 120 includes an antenna 120a located on the upper surface side of the cover 54, and a shaft portion 120b extending downward from the antenna 120a and having an outer diameter smaller than that of the antenna 120a. The cover 54 is formed with a through hole 54a for inserting the shaft portion 120b. In the present embodiment, the through holes 54a are provided in a line in the longitudinal direction of the cover 54. The relay device 120 is arranged with the antenna 120a located on the upper surface side of the cover 54 and the shaft portion 120b inserted into the through hole 54a formed in the cover 54. The relay device 120 is provided individually corresponding to each battery monitoring device 30. The antenna 120a may be covered with a cover that transmits radio waves.

[0187] The through hole 54a is covered by the antenna 120a of the relay device 120. A seal member may be interposed between the antenna 120a and the upper surface of the cover 54.

[0188] The child device side wireless IC 32 of the battery monitoring device 30 and the antenna 120a are electrically connected by a communication wiring provided on the shaft portion 120b. This allows wireless communication between the battery monitoring device 30 and the battery control device 40 via the antenna 120a and the parent device side antenna 43.

[0189] In the present embodiment described above, diffuse reflection of radio waves occurs in the storage unit 105. Furthermore, the communication environment in the storage unit 105 may change due to reuse or the like. For this reason, the configurations described in the above embodiments can be applied.

[0190] <Eleventh embodiment> Hereinafter, the eleventh embodiment will be described with reference to Fig. 43, focusing on the differences from the ninth embodiment. In Fig. 43, the same reference numerals are used for the same or corresponding configurations as those described in the above embodiments for convenience.

[0191] The battery control device 40 is attached to the upper surface of the junction box 15 inside the housing 50. Meanwhile, the first to fourth battery monitoring devices 30A to 30D are arranged outside the housing 50 in the housing section 105, and more specifically, are attached to the upper surface of the cover 54. In this case, in order to perform communication between the battery control device 40 housed inside the housing 50 and each of the battery monitoring devices 30A to 30D arranged outside the housing 50, a configuration for connecting the inside and outside of the housing 50 for communication is required.

[0192] The battery pack 11 of the present embodiment includes a relay device 130 as a communication connection configuration. The relay device 130 includes a connection portion 130b located on the upper surface side of the cover 54, and an antenna 130a extending downward from the connection portion 130b. The cover 54 is formed with a through hole 54a for inserting the antenna 130a. The through holes 54a are arranged in a row in the longitudinal direction of the cover 54. The relay device 130 is provided individually corresponding to each battery monitoring device 30. The antenna 130a may be covered with a cover that transmits radio waves.

[0193] The through hole 54a is closed by the connection portion 130b of the relay device 130. A seal member may be interposed between the connection portion 130b and the upper surface of the cover 54.

[0194] The slave-side wireless IC 32 of the battery monitoring device 30 and the antenna 130a are electrically connected by a communication wiring provided in the connection section 130b. This allows wireless communication between the battery monitoring device 30 and the battery control device 40 via the antenna 130a and the master-side antenna 43.

[0195] In the present embodiment described above, diffuse reflection of radio waves occurs in the storage unit 105. Furthermore, the communication environment in the storage unit 105 may change due to reuse or the like. For this reason, the configurations described in the above embodiments can be applied.

[0196] <Twelfth embodiment> Hereinafter, the twelfth embodiment will be described with reference to Fig. 44, focusing on the differences from the above-mentioned embodiments. In Fig. 44, the same reference numerals are used for the same configurations as or corresponding configurations described in the above-mentioned embodiments for convenience.

[0197] 44, a configuration may be adopted in which the housing 50 is not provided, and the battery blocks 21A-21D, the battery monitoring devices 30A-30D, and the battery control device 40 are directly accommodated in an accommodating portion 105 of the chassis 100. This configuration is called MTP (Module to Platform).

[0198] In the present embodiment described above, diffuse reflection of radio waves occurs in the storage unit 105. Furthermore, the communication environment in the storage unit 105 may change due to reuse or the like. For this reason, the configurations described in the above embodiments can be applied.

[0199] <Other embodiments> Each of the above embodiments may be modified as follows.

[0200] In each of the above embodiments, a configuration is used in which a plurality of battery cells are grouped into a battery block, and then the battery blocks are connected in series. Instead of this configuration, a so-called CTP (Cell to Pack) configuration may be used in which a series connection of a plurality of battery cells is accommodated in the accommodation section 105 of the chassis 100 without creating a battery block. An example of this case is shown in FIG. 45. In the example shown in FIG. 45, a plurality of elongated battery cells 200 that are long in the vehicle width direction are accommodated in the accommodation section 105. Among adjacent battery cells 200, one positive terminal 201 and the other negative terminal 202 are electrically connected by a bus bar (not shown). In this case, for example, a battery monitoring device may be provided individually corresponding to each battery cell 200.

[0201] Also, instead of the CTP configuration, a so-called CTC (Cell to Chassis) configuration may be used in which a housing portion for housing a battery cell is configured on the chassis of the vehicle, and a plurality of battery cells are housed in the housing portion.

[0202] Even in the case of the CTP or CTC configuration, radio waves are reflected by at least a part of the housing. In addition, the communication environment in the housing may change due to reuse, etc. For this reason, there is an advantage in applying the configurations described in the above embodiments.

[0203] The configuration in which the parent device antenna 43 described in the second embodiment is capable of changing the radio wave directivity can be applied to the fourth and subsequent embodiments.

[0204] The mobile object on which the battery monitoring system is mounted is not limited to a vehicle, but may be, for example, an aircraft or a ship. The control system is not limited to a system mounted on a mobile object, but may be a stationary system.

[0205] The control unit and the method described in the present disclosure may be realized by a special-purpose computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control unit and the method described in the present disclosure may be realized by a special-purpose computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and the method described in the present disclosure may be realized by one or more special-purpose computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured with one or more hardware logic circuits. Also, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by the computer.

[0206] Characteristic configurations extracted from each of the above-described embodiments will be described below. [Configuration 1] a battery monitoring device (30, 30A-30D) provided in correspondence with each of the plurality of batteries (21, 21A-21D, 200) and monitoring the state of the battery; A battery control device (40), In a battery monitoring system in which the batteries, the battery monitoring devices, and the battery control device are accommodated in a housing portion (55, 105) configured to reflect radio waves at least in part, The battery control device has a parent-side antenna (43) for wireless communication with the battery monitoring device, Each of the battery monitoring devices has a slave-side antenna (33) for wireless communication with the battery control device, At least one of the radio wave directivities of the radio wave directivities of the antennas on the child device side and the radio wave directivities of the antennas on the parent device side is configured to be selectable from a plurality of radio wave directivities having different directions of the center of the radio wave directivities; A battery monitoring system in which a radio wave directivity is set to one of the radio wave directivities other than the radio wave directivity that provides the lowest communication quality for the wireless communication in a channel used for wireless communication between the parent unit antenna and the child unit antenna. [Configuration 2] The battery monitoring system of configuration 1, wherein, in a channel used for wireless communication between the parent unit antenna and the child unit antenna, among the radio wave directivities, a radio wave directivity is set such that the received power of the battery control device or the battery monitoring device when the wireless communication is performed is equal to or greater than a threshold value (Wmin). [Configuration 3] A battery monitoring system as described in configuration 2, in which, among the radio wave directivities, a radio wave directivity is set in which the received power is maximized and is equal to or greater than the threshold value when the wireless communication is performed, in a channel used for wireless communication between the parent unit side antenna and the child unit side antenna. [Configuration 4] Each of the battery monitoring devices is a slave side storage unit (34) for storing directivity information in which each of a plurality of channels available for wireless communication between the slave side antenna and the master side antenna included in the slave side storage unit (34) is associated with a radio wave directivity in each of the channels in which the received power is equal to or greater than the threshold value when the wireless communication is performed, among the radio wave directivities in each of the channels; A battery monitoring system as described in configuration 2, which sets the radio wave directivity of the child device side antenna that the system owns to a radio wave directivity associated with the channel used in the wireless communication based on the stored directivity information. [Configuration 5] the battery control device, on the condition that a specific condition is determined to be established, transmits, from the parent unit-side antenna to each of the battery monitoring devices, a command to cause each of the battery monitoring devices to transmit a radio signal corresponding to each radio wave directivity from the child unit-side antenna of each of the battery monitoring devices; When each of the battery monitoring devices receives the command via the child device-side antenna, the battery monitoring device transmits a wireless signal from the child device-side antenna to the battery control device; The battery control device receiving, by the parent device side antenna, a wireless signal from the battery monitoring device corresponding to each radio wave directivity, and measuring a reception power for each channel of the wireless signal received by the parent device side antenna; generating the directivity information based on the measured received power, and transmitting the generated directivity information from the parent device side antenna to the battery monitoring device; 5. The battery monitoring system according to claim 4, wherein each of the battery monitoring devices stores the directivity information received by the child unit side antenna in the child unit side memory unit. [Configuration 6] The battery control device includes: a parent device side storage unit (44) for storing directivity information in which each of a plurality of channels available for wireless communication between the parent device side antenna and the child device side antenna is associated with a radio wave directivity in each of the channels in which the received power is equal to or greater than the threshold value when the wireless communication is performed, among the radio wave directivities; A battery monitoring system as described in configuration 2, which sets the radio wave directivity of the parent unit antenna to a radio wave directivity associated with the channel used in the wireless communication based on the stored directivity information. [Configuration 7] the battery control device, on the condition that a specific condition is determined to be established, transmits, from the parent unit-side antenna to each of the battery monitoring devices, a command to transmit a wireless signal from the child unit-side antenna of each of the battery monitoring devices; When each of the battery monitoring devices receives the command via the child device-side antenna, the battery monitoring device transmits a wireless signal from the child device-side antenna to the battery control device; The battery control device When the radio wave directivity of the parent device side antenna is set to each of a plurality of radio wave directivities, a radio signal from the battery monitoring device is received by the parent device side antenna, and a receiving power for each channel of the radio signal received by the parent device side antenna is measured; A battery monitoring system according to configuration 6, further comprising: generating the directivity information based on a measured received power; and storing the generated directivity information in the master unit side memory unit. [Configuration 8] The battery monitoring system of configuration 5 or 7, wherein the specific condition is that the battery monitoring system is started for the first time after each battery, each battery monitoring device, and the battery control device are accommodated in the accommodation section during the manufacturing process of the battery monitoring system or when the batteries constituting the battery monitoring system are reused. [Configuration 9] The battery monitoring system is mounted on a vehicle (10) in which a user can ride, 8. The battery monitoring system according to configuration 5 or 7, wherein the specific condition is that either a moving distance of the moving object or a moving time of the moving object exceeds a judgment value (Lth). [Configuration 10] The battery monitoring system according to configuration 5 or 7, wherein the specific condition is that the arrangement of the batteries, the battery monitoring devices, and the battery control device in the storage section deviates from a predetermined arrangement. [Configuration 11] The battery monitoring system is mounted on a vehicle (10) in which a user can ride, A battery monitoring system as described in configuration 9 or 10, wherein when the battery control device determines that the user has not given an instruction to start the moving body and that the moving body is in a stopped state, and determines that the specific condition is met, it transmits the command from the parent unit antenna to each battery monitoring device. [Configuration 12] An inspection device (300) communicably connected to the battery monitoring device, 8. The battery monitoring system according to claim 5 or 7, wherein the specific condition is that history information of the state of the battery monitored by the battery monitoring device is requested by the inspection device. [Configuration 13] The antenna configured to be able to select radio wave directivity among the parent device side antenna and the child device side antenna is A circuit board (61); an antenna member (67) provided on the circuit board; a plurality of power feed lines (68A to 68D, 74A to 74D) provided on the circuit board, electrically connected to the antenna member, and feeding power to the antenna member; a ground pattern (69A to 69C, 72, 75) provided between adjacent power supply lines on the circuit board; 13. The battery monitoring system according to any one of configurations 1 to 12, comprising: [Configuration 14] A battery monitoring system as described in configuration 1, in which, in a channel used for wireless communication between the parent unit antenna and the child unit antenna, a radio wave directivity is set to one of the radio wave directivities such that a communication error rate when the wireless communication is performed is equal to or lower than a threshold value (Eth). [Configuration 15] The battery monitoring system of configuration 1, wherein, in a channel used for wireless communication between the parent unit antenna and the child unit antenna, among the radio wave directivities, a radio wave directivity is set such that a difference between the received power of the battery control device and the noise floor when the wireless communication is performed is equal to or greater than a threshold value (Wth). [Configuration 16] The present invention is applied to a battery monitoring system including a plurality of batteries (21, 21A to 21D, 200) and a battery control device (40), A battery monitoring device (30, 30A to 30D) that is arranged together with the batteries and the battery monitoring devices in a housing (55, 105) that is configured to reflect radio waves at least in part, the battery monitoring device is provided individually corresponding to each of the batteries and monitors the state of the batteries; Each of the battery monitoring devices has a slave-side antenna (33) for wireless communication with the battery control device, The radio wave directivity of each of the slave unit side antennas is selectable from a plurality of radio wave directivities having different directions of the center of the radio wave directivity, A battery monitoring device, in which, in a channel used for wireless communication between a parent unit side antenna (43) and the child unit side antenna of the battery control device, the radio wave directivity of the child unit side antenna is set to a radio wave directivity other than the radio wave directivity that provides the lowest communication quality of the wireless communication among the respective radio wave directivities. [Configuration 17] The present invention is applied to a battery monitoring system including a battery monitoring device (30, 30A to 30D) provided individually for each of a plurality of batteries (21, 21A to 21D, 200) and monitoring the state of the batteries, A battery control device (40) arranged together with the batteries and the battery monitoring devices in a housing (55, 105) at least a portion of which is configured to reflect radio waves, The battery control device has a parent-side antenna (43) for wireless communication with the battery monitoring device, The parent device side antenna is configured such that its radio wave directivity can be selected from a plurality of radio wave directivities having different directions of the center of the radio wave directivity, A battery control device, in which, in a channel used for wireless communication between the parent unit side antenna and a child unit side antenna (33) possessed by the battery monitoring device, the radio wave directivity of the parent unit side antenna is set to a radio wave directivity among the respective radio wave directivities other than the radio wave directivity that provides the lowest communication quality of the wireless communication. [Explanation of symbols]

[0207] 11...battery pack, 21...battery block, 30...battery monitoring device, 33...child unit side antenna, 40...battery control device, 43...parent unit side antenna, 55...housing section.

Claims

1. a battery monitoring device (30, 30A-30D) provided in correspondence with each of the plurality of batteries (21, 21A-21D, 200) and monitoring the state of the battery; A battery control device (40), In a battery monitoring system in which the batteries, the battery monitoring devices, and the battery control device are accommodated in a housing portion (55, 105) configured to reflect radio waves at least in part, The battery control device has a parent device side antenna (43) for wireless communication with the battery monitoring device, Each of the battery monitoring devices has a slave side antenna (33) for wireless communication with the battery control device, At least one of the radio wave directivities of the radio wave directivities of the antennas on the child device side and the radio wave directivities of the antennas on the parent device side is configured to be selectable from a plurality of radio wave directivities having different directions of the center of the radio wave directivities; A battery monitoring system in which a radio wave directivity is set to one of the radio wave directivities other than the radio wave directivity that provides the lowest communication quality for the wireless communication in a channel used for wireless communication between the parent unit antenna and the child unit antenna.

2. The battery monitoring system of claim 1, wherein, in a channel used for wireless communication between the parent unit side antenna and the child unit side antenna, the radio wave directivity is set to a radio wave directivity such that the received power of the battery control device or the battery monitoring device when the wireless communication is performed is equal to or greater than a threshold value (Wmin).

3. The battery monitoring system of claim 2, wherein, in a channel used for wireless communication between the parent unit side antenna and the child unit side antenna, the radio wave directivity is set to one among the radio wave directivities such that the received power is maximum when the wireless communication is performed and the received power is greater than or equal to the threshold value.

4. Each of the battery monitoring devices is a slave side storage unit (34) for storing directivity information in which each of a plurality of channels available for wireless communication between the slave side antenna and the master side antenna that the slave side storage unit owns is associated with a radio wave directivity in each of the channels in which the received power is equal to or greater than the threshold value when the wireless communication is performed, among the radio wave directivities in each of the channels; The battery monitoring system according to claim 2 , further comprising: a first antenna for a terminal connected to the terminal, the first antenna being connected to the terminal;

5. the battery control device, on the condition that a specific condition is determined to be established, transmits, from the parent unit-side antenna to each of the battery monitoring devices, a command to cause each of the battery monitoring devices to transmit a radio signal corresponding to each radio wave directivity from the child unit-side antenna of each of the battery monitoring devices; When each of the battery monitoring devices receives the command via the child device-side antenna, the battery monitoring device transmits a wireless signal from the child device-side antenna to the battery control device; The battery control device receiving, by the parent device side antenna, a wireless signal from the battery monitoring device corresponding to each radio wave directivity, and measuring a reception power for each channel of the wireless signal received by the parent device side antenna; generating the directivity information based on the measured received power, and transmitting the generated directivity information from the parent device side antenna to the battery monitoring device; The battery monitoring system according to claim 4 , wherein each of the battery monitoring devices stores the directivity information received by the slave-side antenna included in the respective battery monitoring devices in the slave-side storage unit.

6. The battery control device includes: a parent device side storage unit (44) for storing directivity information in which each of a plurality of channels available for wireless communication between the parent device side antenna and the child device side antenna is associated with a radio wave directivity in each of the channels in which the received power is equal to or greater than the threshold value when the wireless communication is performed, among the radio wave directivities; The battery monitoring system according to claim 2 , further comprising: setting, based on the stored directivity information, the radio wave directivity of the parent device side antenna to a radio wave directivity associated with a channel used in the wireless communication.

7. the battery control device, on the condition that a specific condition is determined to be established, transmits, from the parent unit-side antenna to each of the battery monitoring devices, a command to transmit a wireless signal from the child unit-side antenna of each of the battery monitoring devices; When each of the battery monitoring devices receives the command via the child device-side antenna, the battery monitoring device transmits a wireless signal from the child device-side antenna to the battery control device; The battery control device When the radio wave directivity of the parent device side antenna is set to each of a plurality of radio wave directivities, a radio signal from the battery monitoring device is received by the parent device side antenna, and a receiving power for each channel of the radio signal received by the parent device side antenna is measured; The battery monitoring system according to claim 6 , wherein the directivity information is generated based on a measured received power, and the generated directivity information is stored in the master unit side storage unit.

8. The battery monitoring system of claim 5 or 7, wherein the specific condition is that the battery monitoring system is started for the first time after each battery, each battery monitoring device, and each battery control device are accommodated in the accommodation section during the manufacturing process of the battery monitoring system or when the batteries constituting the battery monitoring system are reused.

9. The battery monitoring system is mounted on a vehicle (10) in which a user can ride, 8. The battery monitoring system according to claim 5, wherein the specific condition is that either a moving distance of the moving object or a moving time of the moving object exceeds a threshold value (Lth).

10. The battery monitoring system according to claim 5 or 7, wherein the specific condition is that an arrangement state of the batteries, the battery monitoring devices, and the battery control device in the housing portion has deviated from a predetermined arrangement state.

11. The battery monitoring system is mounted on a vehicle (10) in which a user can ride, The battery monitoring system of claim 10, wherein the battery control device, when it determines that the user has not given an instruction to start the moving body and that the moving body is in a stopped state, and when it determines that the specific condition is met, transmits the command from the parent unit antenna to each of the battery monitoring devices.

12. An inspection device (300) communicably connected to the battery monitoring device, 8. The battery monitoring system according to claim 5, wherein the specific condition is that history information on the state of the battery monitored by the battery monitoring device is requested by the inspection device.

13. The antenna configured to be able to select radio wave directivity among the parent device side antenna and the child device side antenna is A circuit board (61); An antenna member (67) provided on the circuit board; a plurality of power feed lines (68A to 68D, 74A to 74D) provided on the circuit board, electrically connected to the antenna member, and feeding power to the antenna member; a ground pattern (69A to 69C, 72, 75) provided between adjacent power supply lines on the circuit board; The battery monitoring system according to any one of claims 1 to 7, comprising:

14. The battery monitoring system of claim 1, wherein, in a channel used for wireless communication between the parent unit side antenna and the child unit side antenna, the radio wave directivity is set to one among the radio wave directivities such that the communication error rate when the wireless communication is performed is equal to or lower than a threshold value (Eth).

15. The battery monitoring system of claim 1, wherein, in a channel used for wireless communication between the parent unit antenna and the child unit antenna, the radio wave directivity is set to one among the radio wave directivities such that the difference between the received power of the battery control device and the noise floor when the wireless communication is performed is equal to or greater than a threshold value (Wth).

16. The present invention is applied to a battery monitoring system including a plurality of batteries (21, 21A to 21D, 200) and a battery control device (40), A battery monitoring device (30, 30A to 30D) arranged together with the batteries and the battery monitoring devices in a housing (55, 105) at least a portion of which is configured to reflect radio waves, the battery monitoring device is provided individually corresponding to each of the batteries and monitors the state of the batteries; Each of the battery monitoring devices has a slave side antenna (33) for wireless communication with the battery control device, The radio wave directivity of each of the slave unit side antennas is selectable from a plurality of radio wave directivities having different directions of the center of the radio wave directivity, A battery monitoring device, in which, in a channel used for wireless communication between a parent unit side antenna (43) and a child unit side antenna possessed by the battery control device, the radio wave directivity of the child unit side antenna is set to a radio wave directivity among the respective radio wave directivities other than the radio wave directivity that provides the lowest communication quality of the wireless communication.

17. The present invention is applied to a battery monitoring system including a battery monitoring device (30, 30A-30D) provided individually for each of a plurality of batteries (21, 21A-21D, 200) and monitoring the state of the batteries, A battery control device (40) arranged together with the batteries and the battery monitoring devices in a housing (55, 105) at least a portion of which is configured to reflect radio waves, The battery control device has a parent device side antenna (43) for wireless communication with the battery monitoring device, The parent device side antenna is configured such that its radio wave directivity can be selected from a plurality of radio wave directivities having different directions of the center of the radio wave directivity, A battery control device, in which, in a channel used for wireless communication between the parent unit side antenna and a child unit side antenna (33) possessed by the battery monitoring device, the radio wave directivity of the parent unit side antenna is set to a radio wave directivity among the respective radio wave directivities other than the radio wave directivity that provides the lowest communication quality of the wireless communication.

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